The present invention relates to point-of-use water treatment system (WTS) units used in homes and offices to filter and treat contaminants in water.
The present invention minimizes or overcomes several problems associated with previous point-of-use home or office water treatment system (WTS) units. A first problem is that conventional WTS units, utilizing lamp assemblies with UV bulb assemblies therein, are energy inefficient. When a conventional lamp assembly is turned on, it takes a significant amount of start-up time before gases within a UV bulb assembly are sufficiently excited to output light of an intensity level required to insure adequate destruction of microorganisms within the WTS unit. Water which is discharged from the WTS unit before a UV bulb assembly is sufficiently excited and microorganisms properly irradiated may carry an unacceptably high level of live microorganisms. Consequently, conventional lamp assemblies are left continuously running which uses a significant amount of energy. Also, with the lamp assembly left running continuously, such as overnight, water residing within a WTS unit can become uncomfortably warm. Finally, the life expectancy of a lamp assembly which is kept running continuously is significantly reduced relative to a lamp assembly which is only activated when water is to be treated.
A second problem is with the design of reflector assemblies within WTS units. In an attempt to increase lamp efficiency, reflector assemblies may be placed about UV bulb assemblies and water carrying conduits in which the microorganisms are irradiated. Light emitted from a UV bulb assembly which misses striking water carrying conduits is reflected back from the reflectors walls and has a chance to again impinge upon the water carrying conduits. These reflector assemblies may be circular in cross-section. Unfortunately, a lot of the UV light produced by these circular reflector designs never reaches the water carrying conduits. Rather, a significant portion of reflected light is reabsorbed by the UV bulb assembly and never reaches the water carrying conduit.
A third problem involves the electrical coupling of the lamp assemblies to WTS units. Every time a lamp assembly is installed in or removed from a WTS unit, the lamp assembly must be mechanically and electrically coupled and uncoupled relative to the WTS unit. This often required complicated and expensive electrical mounting assemblies. Further, care must be taken to insure that the electrical connections are not exposed to moisture while electrical power is passing through the WTS unit.
Coaxially aligned lamp assemblies and filter assemblies are sometime used to minimize the size of WTS units. A lamp assembly and filter assembly in a particular WTS may or may not be simultaneously removed from the WTS unit. If these assemblies are simultaneously removed, they are often very quite heavy as they may have substantial weight on their own and may be filled with water. Alternatively, even if the lamp and filter assemblies are separably removably from a WTS unit, quite often problems exist of water spilling from one of these assemblies during handling.
Another problem faced by WTS units having UV lamp assemblies is that complicated monitoring systems are needed to monitor the lamp assemblies. As a lamp assembly ages, the intensity of UV light output from the lamp assembly generally diminishes. Eventually, the intensity falls below a level necessary to effect a desired microorganism kill rate. The lamp assembly should be replaced before the desired minimum intensity is reached. Accordingly, a monitoring system is required to check on the UV light intensity within the WTS unit. These monitoring systems are typically expensive. They often require costly UV light sensors with quartz windows.
Point-of-use water treatment systems are typically left running continuously due to microorganism growth that would otherwise occur if the systems were shut down. Lamp assemblies in typical WTS units require a relative long time to reach a threshold value of emitted radiation intensity needed to attain a desired kill rate. Accordingly, water containing unacceptably high levels of live microorganisms may be delivered from a WTS unit before that threshold value of light intensity is reached.
Other problems and deficiencies that typical WTS units have include complicated assembly and locking mechanisms for mounting filter and lamp assemblies which may include nuts, bolts and O-rings which must be manually installed.
These and other deficiencies in prior WTS units employing lamp assemblies and filter assemblies are overcome by the present invention.
The present invention includes a point-of-use water treatment system which has a base unit, a filter assembly with an inner sleeve and a secondary water treatment device such as a UV lamp assembly. The inner sleeve provides a chamber for the secondary water treatment device. Ideally first and second valves and seals provide control of the flow of water between the filter assembly and the secondary water treatment device and between the secondary water treatment device and the base unit. The valves and seals prevent unwanted water spillage when the filter assembly and lamp assembly are removed and replaced from the base unit.
The present invention also includes a lamp assembly, preferably for use in a water treatment system that includes a bulb assembly, a reflector assembly and a conduit carrying water through the lamp assembly. The reflector assembly is configured or shaped to reflect and focus light emitted from the bulb assembly onto the conduit and away from returning to the bulb assembly thereby enhancing the efficiency of the lamp assembly.
The present invention further includes a replaceable lamp assembly, which includes a water-carrying conduit captured between a pair of ends caps and a bulb assembly for irradiating the conduit. The conduit serves as a reactor vessel in which microorganism and other contaminants may be treated. Enclosures may be used which cooperate with the end caps to form a generally closed vessel surrounding the UV bulb assembly and conduit. The lamp assembly may also include two or more conduits extending between the end caps. The lamp assembly is generally self-contained and can be readily installed in a test fixture or in the water treatment system.
Another aspect of the present invention is the use of condensing element to cool an intermediate portion of a bulb assembly between its filaments. The intermediate portion, which is cooled, allows a condensable material, such as mercury, to condense onto the intermediate portion of the bulb between filaments. When the lamp assembly is energized, the condensed mercury can quickly be revaporized as it lies in the arc path between the filaments. Otherwise, when the condensed mercury is located outside the arc path, the condensed mercury requires a greater time to become fully vaporized when the lamp assembly is reenergized. This condensing of the mercury in the arc path assists the lamp assembly in reaching a threshold intensity level in a shorter period of time. A condensing element extending between the bulb and a conduit carrying cool water can serve as a heat sink to cool the intermediate portion of the bulb in contact with the condensing element. If the condensing element is elastomeric, the condensing can also serve a cushioning functioning.
Yet another feature of the present invention is the use of a plastic light pipe impregnated with a florescent dye to convert UV light into visible light. This conversion allows the relative intensity of the UV light produced by a lamp assembly to be easily measured by an inexpensive visible light detector. The light pipe may include polished and angled surfaces to receive incident UV light and cause the light pipe to emit visible light at a particular emitting surface wherein the visible light may be measured for intensity. Preferably, the florescent dye is in the green wavelength of color.
An additional feature is the use of an inductively coupled base unit and lamp assembly to provide UV radiation necessary to kill microorganism passing through a water treatment system. Also, radio frequency identification (RFID) and communication between smart chips on the base unit, filter assembly and lamp assembly can provide information regarding operation of the water treatment system such as filter and lamp life and usage, identification of a particular filter assembly or lamp assembly, and other desired information. The use of inductive coupling and RFID allows the filter assembly and lamp assembly to operate without any hard wiring to a base unit. The base unit will include microprocessors to control the operation of the water treatment system.
It is an object of the present invention to provide a WTS unit which requires no direct physical electrical connection between a removable lamp assembly and a base unit which powers the lamp assembly.
It is another object to provide a WTS unit having a base unit with a primary coil and a lamp assembly with a secondary coil, the primary coil supplying energy to the secondary coil to power the lamp assembly such that a high intensity UV light is to produced within the WTS unit.
A further object is to provide a reflector assembly in a WTS unit wherein the UV light produced by a UV bulb assembly is reflected and focused upon one or more conduits carrying water to be treated while minimizing reflected light striking and being absorbed by the UV bulb assembly.
It is an additional object to provide a WTS unit wherein a filter assembly cooperatively mounts to a base unit and to a lamp assembly to allow water to pass through the filter assembly and wherein when the filter assembly is removed from the base unit and lamp assembly, the filter assembly is self-sealing preventing water from spilling from the filter assembly.
Yet another object is to provide a WTS unit having a ballast and lamp assembly wherein a UV bulb assembly, upon start up, can virtually instantaneously produce UV light of sufficiently high intensity such that the lamp assembly can be run intermittently while maintaining desired microorganism kill rates.
Still yet another object is to provide a WTS unit which runs intermittently and has a UV bulb assembly with a pair of spaced apart filaments and a heat sink in contact with the UV bulb assembly such that a cool spot on the UV bulb assembly is formed between the filaments wherein at least one of the ionized gases will condense adjacent the cool spot between the filaments when the UV bulb assembly is deenergenized. This allows the condensed gas to be quickly reionized when the UV bulb assembly is reenergized.
Still yet another object is to provide a light pipe which receives UV light, fluoresces and outputs visible light generally linearly proportional in intensity to the incoming UV light.
An additional object is to provide smart chips in one or more of filter and lamp assemblies which transponds with an electrical assembly on a base unit to record usage information from the filter and lamp assemblies.